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THE MUSCULAR SYSTEM                 173
greater and lesser cornua. It fuses with its neighbour in the mid-dorsal line, and it is overlapped by the inferior constrictor pharyngis. The latter arises from the oblique line on the thyroid cartilage and from the side of the cricoid, but it does not arise from the first tracheal ring, as stated by G-ratioIet (330). It is inserted along with its neighbour into the mid-dorsal line of the pharynx.
The stylo-pharyngeus (fig. O!BI arises from the styloid process or from the tendon of the stylo-glossus. It enters the pharyngeal wall with or without sending bundles into the superior and middle constrictor muscles. The glosso-pharyngeal nerve hooks round it as in Man.
The levator palati and tensor palati (fig. 30, B) are disposed as in Man, but their origins may be separate or fused. They are more horizontal than in Man owing to the prognathism of the jaws. The levator (L.P.) passes in between the layers of the palato-pharyngeus and the tensor (T.P.) hooks round the pterygoid hamulus. The azygos uvulae (A.U.) runs from the hard palate or posterior nasal spine to the uvula.
Scaleni.—The scalenus anticus, lying in front of the brachial plexus, arises from the anterior tubercles of the transverse processes of cervical vertebrae 3 to 5 or 4 to 6 ; and it is inserted into the scalene tubercle on the first rib. The scalenus niedius and posticus are combined in one sheet, which extends to the second or third rib; but I observed it going to the fifth rib in a Chimpanzee. It may be strongly fused with the ilio-costalis cervicis.
The omo-trachelian, which is absent in Man, runs from the transverse process of the atlas to the upper and outer aspect of the acromion process.